Volume 3, Issue 10 (November 2006)
Effect of Entrained Air on Recycled Concrete Prasoperties
Air entrainment is a good practice to improve the durability of concrete exposed to cycles of freezing and thawing. For a given admixture dosage, the air content will depend on mix proportions and the characteristics of the materials employed. The use of crushed waste concretes (recycled coarse aggregates), which have different characteristics and properties compared to natural coarse aggregates, could modify the air content and behavior of recycled concretes. In this paper, some fresh and hardened state properties of entrained air recycled concretes were evaluated and compared with those of entrained air conventional concrete. Recycled concretes were elaborated with 50, 75, and 100% replacement by volume of natural coarse aggregates by crushed waste concretes. The results indicate that the recycled concretes show a satisfactory mechanical and durable behavior, similar to or better than that of conventional one.